• DOI:10.1063/1.5084219
• Corpus ID: 89618175

Micro-Faraday cup matrix detector for ion beam measurements in fusion plasmas.

@article{Rfy2019MicroFaradayCM,
  title={Micro-Faraday cup matrix detector for ion beam measurements in fusion plasmas.},
  author={D I R{\'e}fy and S{\'a}ndor Zoletnik and D{\'a}niel Dunai and G Anda and M. Lampert and S. Hegedűs and D. Nagy and Mikl{\'o}s Pal{\'a}nkai and Jenő K{\'a}di and B Lesk{\'o} and M. Aradi and P. H{\'a}{\vc}ek and Vladimir Weinzettl},
  journal={The Review of scientific instruments},
  year={2019},
  volume={90 3},
  pages={
          033501
        }
}

• D. Réfy, S. Zoletnik, +10 authors V. Weinzettl
• Published 1 March 2019
• Physics
• The Review of scientific instruments

Atomic beam probe is an extension of the routinely used beam emission spectroscopy diagnostic for the plasma edge current fluctuation measurement at magnetically confined plasmas. Beam atoms ionized by the plasma are directed to a curved trajectory by the magnetic field and may be detected close to the wall of the device. The arrival location and current distribution of the ions carry information about the plasma current distribution, the density profile, and the electric potential in the plasma edge. This paper describes a micro-Faraday cup matrix detector for the measurement of the few microampere ion current distribution close to the plasma edge. The device implements a shallow Faraday cup matrix, produced by printed-circuit board technology. Secondary electrons induced by the plasma radiation and the ion bombardment are basically confined into the cups by the tokamak magnetic field. Additionally, a double mask is installed in the front face to limit the ion influx into the cups and supplement secondary electron suppression. The setup was tested in detail using a lithium ion beam in the laboratory. Switching time, cross talk, and fluctuation sensitivity test results in the lab setup are presented along with the detector setup to be installed at the COMPASS tokamak.